太湖上游流域经济发展对废水排放及入湖总磷的影响

Effects of economic development on wastewater discharge and influent total phosphorus load in the upstream of Lake Taihu Basin

为探索太湖流域水环境质量随经济发展的变化趋势，利用环境库兹涅茨曲线模型模拟1978—2012年太湖上游流域人均GDP与废水排放量、入湖总磷负荷的关系．结果表明：以1978年为计算基期，太湖上游流域人均GDP年均增速为10．3％～11．8％；1990—2012年，太湖上游流域年均工业废水排放量和废水排放总量分别为64799×10^4、93707×10^4t，与人均GDP均呈倒U型关系，从2006—2007年、2008—2009年呈下降趋势；人湖总磷负荷与太湖上游流域废水排放总量呈显著正相关，且与人均GDP呈倒U型关系，从2007—2008年呈下降趋势，在1990s以前为850～1200t／a，1990s以后为1300—2000t／a．该研究为从经济学角度评估太湖上游流域废水排放、入湖总磷负荷及其变化趋势提供科学依据．

In the upstream Lake Taihu Basin, economic development affects the discharge amount of wastewater and influent total phosphorus （TP） load. In order to reveal the trend of water environment quality with economy in the Lake Taihu Basin, we simula- ted the relationships between wastewater discharge, influent TP load and Gross Domestic Product （GDP） per capita for the up- stream Lake Taihu Basin （1978 -2012） using Environmental Kuznets Curve （EKC） models. The results showed that the average annual growth rate of GDP per capita was 10.3% - 11.8% based on 1978 prices in the upstream Lake Taihu Basin. Meanwhile, during 1990 -2012, the annual mean discharge amount of industrial wastewater and the annual mean total discharge amount of wastewater were 647.99 million tons and 937.07 million tons, respectively. The export of EKC models revealed that both of indus- trial wastewater and total wastewater discharge had inverted-U-shaped relationships with GDP per capita, and decreased during 2006 - 2007 and 2008 -2009, respectively. Moreover, influent TP load was positively related with the total wastewater discharge in the upstream of Lake Taihu Basin, presenting an inverted-U-shaped relationship with GDP per capita and declining during 2007 -2008. During 1978 -2012, the influent TP load ranged from 850 t/a to 1200 t/a before 1990s; increased to 1300 -2000 t/a after 1990s. The EKC models provided scientific evidence for estimating wastewater discharge and the influent TIP load as well as their changeable trends for the upstream Lake Taihu Basin from an economic perspective.